The unvaccinated people primarily hurt themselves with their own stupidity. Point is, a measles vaccine greatly reduces the odds of you coming down with measles, even if you still get measles with the vaccine in you, which does happen, you tend to have a shorter, milder case. The other factor to consider about measles is that if you go through life until adulthood with zero measles exposure until adulthood, your first exposure can be really dangerous.
Even moreso, thimerosol is no longer used in MMR vaccines.
I wish it were true that the unvaccinated only would endanger themselves by refusing to take vaccines, but the fact is, they endanger many people besides themselves. Some people do not respond to vaccines, or they don't respond equally well to every vaccine, so might not have immunity even after vaccination. Many vaccines cannot be given to small children or infants. Immunity can wane over time, and adults sometimes forget to get boosters. Some people cannot receive vaccines at all. And so on. The best protection for the people who don't become immune or are immunosuppressed or cannot take vaccines is for everyone to be vaccinated, to develop herd immunity. When people refuse vaccination, they compromise herd immunity.
If the anti-vaxxers only endangered themselves, I probably wouldn't care about their refusal to take vaccines.